Answer:
65.1g of O2 will be needed
Explanation:
The equation for the reaction is given below:
C3H8 + 5O2 —>3CO2 + 4H2O
Molar Mass of C3H8 = (3x12) + (8x1) = 36 + 8 = 44g/mol
Molar Mass of O2 = (16x2) = 32g/mol
Mass conc. of O2 from the balanced equation = 5 x 32 = 160g
From the above calculations, we can easily find the mass of O2 needed to completely burn 17.9 g C3H8. This can be done by the following:
From the equation,
44g of C3H8 was completely burnt by 160g of O2.
Therefore,
17.9g of C3H8 will be burnt by Xg of O2. i.e
Xg of O2 = (17.9x160) / 44 = 65.1g
